1. Field of the Invention
The invention relates to devices and methods for moving substrates and other objects, and more particularly, for moving sheets of paper using ratchets secured to a vibrating base element.
2. Description of Related Art
Devices for moving substrates, such as sheet feeders in printers and photocopying machines, commonly are used to move a sheet of paper into a position suitable for printing. Typically, a plurality of spaced rollers engage the sheet and move it into a desired position relative to a printing area. Directional control of the sheet typically is accomplished by moving the supports on which the rollers are mounted, and/or skewing the rollers on their supports.
Such devices, however, generally require drive motors for rotating the rollers and moving the frames that support the rollers. These drive motors often are relatively massive, generate large amounts of thermal energy, and have large power requirements. Further, these devices advance sheets at relatively slow speeds and lack precision in advancing sheets into a desired position.
A need has arisen, therefore, for devices and methods that advance substrates at high speed and precision, while affording greater compactness and efficiency.